Bottom Line:
While live attenuated influenza vaccines are among the most efficacious and can be manufactured at low cost, they may require lyophilization to be stable enough for developing-country use, which adds a significant cost burden.In this study, potential stabilizing excipients were screened and optimized using the least stable influenza vaccine strain presently known, H1N1 (A/California/07/2009), as a model.Through this process, we identified a liquid formulation consisting of sucrose phosphate glutamate buffer with 1% arginine and 0.5% recombinant human serum albumin that provided storage stability of one year at 2-8°C for the influenza A and B strains tested.

fig0005: Screening of excipients. Formulations were prepared with LAIV H1N1 (A/California/07/2009) in SPG buffer and additional excipients were prepared at a titer of 2Â Ã—Â 106Â log10Â TCID50/mL. The formulations were stored at 2â€“8Â Â°C (A) and 25Â Â°C (B), and their titer was measured by TCID50. Formulations were tested for up to 6 weeks or until a titer loss greater than 1 log was observed. NÂ =Â 1 for each formulation tested by TCID50 in triplicate. Error bars represent the standard deviation of three TCID50 replicates. Abbreviations: BSA; bovine serum albumin.

Mentions:
In the first formulation stage, excipients were screened for their ability to improve the stability of LAIV compared to the vaccine in SPG buffer alone, as assessed by TCID50 (Fig. 1). All formulations were stable at 2â€“8Â Â°C for 6 weeks (Fig. 1A). The addition of 1% arginine (Formulation 9) improved the stability of LAIV compared to SPG buffer alone (Formulation 1) at 25Â Â°C. Sorbitol was the worst-performing excipient at 25Â Â°C for both concentrations tested (Fig. 1B). Arginine and BSA were selected as the best-performing excipients for further evaluation.

fig0005: Screening of excipients. Formulations were prepared with LAIV H1N1 (A/California/07/2009) in SPG buffer and additional excipients were prepared at a titer of 2Â Ã—Â 106Â log10Â TCID50/mL. The formulations were stored at 2â€“8Â Â°C (A) and 25Â Â°C (B), and their titer was measured by TCID50. Formulations were tested for up to 6 weeks or until a titer loss greater than 1 log was observed. NÂ =Â 1 for each formulation tested by TCID50 in triplicate. Error bars represent the standard deviation of three TCID50 replicates. Abbreviations: BSA; bovine serum albumin.

Mentions:
In the first formulation stage, excipients were screened for their ability to improve the stability of LAIV compared to the vaccine in SPG buffer alone, as assessed by TCID50 (Fig. 1). All formulations were stable at 2â€“8Â Â°C for 6 weeks (Fig. 1A). The addition of 1% arginine (Formulation 9) improved the stability of LAIV compared to SPG buffer alone (Formulation 1) at 25Â Â°C. Sorbitol was the worst-performing excipient at 25Â Â°C for both concentrations tested (Fig. 1B). Arginine and BSA were selected as the best-performing excipients for further evaluation.

Bottom Line:
While live attenuated influenza vaccines are among the most efficacious and can be manufactured at low cost, they may require lyophilization to be stable enough for developing-country use, which adds a significant cost burden.In this study, potential stabilizing excipients were screened and optimized using the least stable influenza vaccine strain presently known, H1N1 (A/California/07/2009), as a model.Through this process, we identified a liquid formulation consisting of sucrose phosphate glutamate buffer with 1% arginine and 0.5% recombinant human serum albumin that provided storage stability of one year at 2-8°C for the influenza A and B strains tested.